(1) Windows XP is an operating system
(2) Linux is owned and sold by Microsoft
(3) Photoshop is a graphical design tool by Adobe
(4) Linux is free and open source software
(5) Linux is an operating system

(1) A set of programs which control computer working
(2) The way a user operates the computer system
(3) Conversion of high level language to machine language
(4) The way computer operator works
(5) A set of programs which control computer networking